Red Sea Reef Care Nitrate NO3 and Phosphate PO4 Reducer

• Reduces NO3 and PO4 together – one product addresses both, rather than dosing separate media for each.
• Controllable – the daily dose is set by your measured nitrate level, not a fixed schedule, so you're not overshooting into an algae-starved tank.
• Works with your skimmer – efficient protein skimming is what actually exports the bacterial biomass this product grows.
• Wide size range – from a 100 mL trial size for nano tanks up to 5 L for larger systems on ongoing carbon dosing.
• Forgiving of an accidental overdose – Red Sea states a large accidental overdose shouldn't cause irreversible harm, provided the skimmer is adequately rated.

Dose is set by your measured nitrate level, not a flat rate. For mixed reef, marine fish and frag tanks:

SPS-dominant and ultra-low nutrient systems (ULNS) run lower thresholds – test more often and dose more conservatively. Dose daily and consistently; if you miss a day, resume at the current dose rather than doubling up to catch up. If nitrate or phosphate drops below your target range, cut the daily dose by 50% immediately rather than stopping outright.

Do I need a protein skimmer to use this?

Yes. Efficient skimming provides the oxygenation the bacterial population needs and removes the biomass it produces – without it, dosing carbon can do more harm than good.

Because the dose depends on measured nitrate rather than a fixed rate, coverage here is best read as tank litres you can keep dosed for 30 days at the highest maintenance rate (3 mL per 100 L daily, for tanks running above 10 ppm NO3) – the conservative, worst-case reading of the dosing table. On that basis, a 100 mL bottle covers a 111 L tank for 30 days; the 5 L pack covers a 5,556 L equivalent for the same 30 days. Lower nitrate readings stretch every size further than these figures show.

Suitable for marine and reef aquariums with an efficient, correctly-sized protein skimmer, where nitrate or phosphate needs reducing without resin media. Not suitable for tanks without adequate skimming – the bacterial biomass this product produces needs somewhere to go. Not a quick fix for an algae outbreak already underway; it works alongside, not instead of, addressing the nutrient source.

Safe for fish, coral and microfauna when dosed as directed. Keep out of reach of children and pets. Store away from direct sunlight. A large accidental overdose is unlikely to cause irreversible damage provided the skimmer is adequately rated, but should still be corrected back to the measured-dose routine as soon as it's noticed.

• Red Sea Reef Foundation Pro Multi Testing Kit – for measuring NO3 and PO4 before setting your daily dose.
• Red Sea Reef Care KH/Alkalinity Foundation B – a stable, well-skimmed reef still needs its alkalinity dosed separately.

Covered by the manufacturer's standard consumer guarantees in addition to your rights under Australian Consumer Law. Standard parcel delivery Australia-wide.

How quickly will this reduce my nitrate and phosphate?

Gradually – it's designed for controlled, ongoing reduction rather than a rapid fix, and dosing too aggressively risks crashing both nutrients at once.

Can I use this without a protein skimmer?

Not recommended. Without efficient skimming, the bacterial biomass the product produces has nowhere to go and can cloud the water or strip oxygen.

What happens if I dose too much by accident?

Red Sea states a large accidental overdose shouldn't cause irreversible damage with an adequately rated skimmer running, but you should return to the measured-dose routine immediately and watch oxygenation closely.

Is this safe for a tank with fish only, no coral?

Yes – it's stated safe for fish, coral and microfauna, so it works in a fish-only or mixed system as well as a reef.

Which size should I start with?

The 100 mL trial size is a way to confirm the method works for your tank before committing to a larger pack.